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Both of the case studies below, though different, offer valuable insights into the realities of using engineering knowledge and skills to help people struck by disaster. Institution members interested in using their skills in post-disaster situations should read them with care, and reflect on how they relate to the Institution’s guidance on working in the humanitarian or development sectors.
Case study one
The first case study summarises the role that a specialist engineering organisation employing professional engineers can play in post-earthquake reconstruction. It highlights the importance of strong community participation in the design and construction of new houses. It is based on experience and learning from the work of Build Change. It focusses on the selection of materials and structural form, and the implementation and communication of good construction practices. It demonstrates that:
Development efforts need to be based on what communities identify as being of most help to them. This can be achieved through good research and integration with existing efforts
Understanding the context within the country and communities is incredibly important. Projects need to always consider the long-term impacts on the community and how they will be able to use/benefit from new technologies going forward
Being willing to adapt your designs in response to community preferences and feedback is vital. Homeowners should be heavily involved in the design process with the end building incorporating their preferences
We are grateful to Alastair Norris and Build Change for contributing this case study to the Humanitarian and International Development Panel’s guidance.
Case study two
The second case study summarises the experience of an individual engineer working as a volunteer on an impromptu post-earthquake response project. It sets out the significant obstacles that arise when undertaking construction and engineering projects.This applies in both times of crisis and in countries and contexts which are very different to those known by the engineers.
This case study demonstrates clearly how despite the technical aspects of a project being conceptually simple, the realities of the project’s execution never are. It demonstrates the importance of local knowledge and capacities and that good intentions, though important, are not enough by themselves. The situations set out in the case study are typical of those encountered by voluntary projects around the world.
We are grateful to Franky Ken for contributing this insightful case study to the Humanitarian and International Development Panel’s guidance.
By Alastair Norris, Build Change Risk and Resilience Program Manager in Nepal
How engineering needs to adapt to the development context
Engineering in a development context can often be extremely challenging. This is due to the lack of materials, limited skills in engineering and construction, available budgets and perceptions of communities. The latter of these can pose a hidden risk to any project. It is often overlooked by engineers wanting to make a difference in the world, especially following a disaster.
Using Nepal as an example, this case study explores how communities must be included in all engineering projects, especially those that are focussed on the reconstruction of houses and other community infrastructure. Externally designed (engineering) solutions, with no control given to people who use them, have no place in good development practice. This case study highlights some key aspects that need to be considered and should enable sustainable engineering, whilst promoting an environment of innovation.
The case study will discuss different ways to ensure the inclusion of communities; however, it should be remembered that there is no such thing as a single community. In reality a community is actually made up of multiple smaller communities with limited, clearly delineating features and often hidden lines of inclusion and exclusion. Therefore, in practice identifying and working with the community is often much more complex than it appears on paper.
Nepal was struck by a Mw7.8 magnitude earthquake on 25 April 2015. The earthquake caused widespread damage to structures across a large part of the country. Post-earthquake damage surveys showed that over one million private houses were damaged, along with a huge number of schools, community buildings and other infrastructure.
The national and international efforts to construct new houses or retrofit existing houses has been huge. The Nepali government’s National Reconstruction Authority (NRA) has taken the lead. The NRA employs a large number of engineers, spread across the earthquake affected districts, who are tasked with overseeing construction. Part of their work is to approve that every house is constructed compliantly and this is done at three specific stages. Once signed off by the engineer the homeowner can then receive the next tranche of their government funded housing grants, which total approximately $3,000 for a finished building.
1. Understanding communities and their way of life
When constructing buildings it is imperative that the local community are involved throughout the whole planning and construction process. This allows the community to understand and influence:
How the building is constructed
How the building needs to be maintained
Whether it is possible to safely alter the structure in the future, and
To accept the building and technology
Without this the building is at risk from being abandoned or, worse still, posing users greater risk due to inadequate maintenance over the following years.
To ensure the building is accepted by the community and that they take full ownership of it, there are certain important community aspects that a project needs to consider.
Context of houses within people’s lives
Before starting design work engineers need to understand how houses are used by all the family, how they enable livelihoods and what attachment people have with existing structures.
The engineers should ask questions like:
How do women, men, girls and boys perceive and use their houses so that they become not just a house, but a home and a place of safety?
Do buildings fulfil needs in addition to keeping people safe and protected from the elements?
What are the different floors of the house used for and how do the users want the space divided up?
The predominant building type in the mountainous regions of Nepal is unreinforced stone masonry in mud mortar (SMM) using unworked rubble stone. This housing is typically 2 to 2.5 storeys in height (two storeys plus attic) with a pitched roof and on plan approximately 50m2. There is a single room on each storey and the storey height is approximately 2.1m. These buildings are highly vulnerable to damage and destruction from seismic events due to the lack of effective connections and having heavy walls with poor mechanical properties.
The houses typically accommodate two or more generations of a family with everyone sharing the same space. Traditionally, women have spent most time in the house looking after the children, socialising and cooking, whilst men have worked the fields. However, the earthquake has in some cases changed this as a higher number of women are being employed as unskilled masons in the reconstruction and therefore spending less time in the house. The ground floor is typically used for livestock. The first floor is used for sleeping and eating and the attic for cooking and storing food from the harvest.
Families have a close affinity with their traditional homes. The buildings are designed to fulfil the many requirements of their agrarian lifestyle. Therefore, new designs which are more resilient to earthquakes need to ensure:
That people’s way of life can be maintained
That designs are possible to construct using local labour
That any modifications homeowners identify as being required for their future lifestyles are accommodated
For example, in Nepal urbanization is very high and therefore the number of people living in each house is reducing. This means less space is required than in previous generations.
An understanding for how construction technology fits into the social context
Houses are affected by the social and psychological perceptions of communities. Certain types of construction might be perceived as strong, safe and durable due to their inherent weight and solidity. Others using lightweight or new materials may be perceived as less strong and lacking durability. These perceptions are always founded on something real. This is normally from something a person has seen first-hand or been told in the past.
It is essential to listen to communities’ opinions and explore the reasoning behind their views. There are often sound motives supporting their thinking that may not be immediately obvious. In other cases, for example when introducing a new material or a technological change to an existing system, communities may have a fixed perception that may be difficult to change. It is however possible to overcome this challenge if sufficient time is spent on awareness (see point 3).
Traditional Nepalese masonry buildings are perceived as being strong. This is due to their inherent weight and the strength of the main constituent element, stone. However, as explained above these buildings can be very vulnerable to earthquakes. As part of the reconstruction within Nepal there has needed to be a large amount of education of communities on how these materials, or similar heavy materials like brick and block, can be used safely.
In Nepal many traditional construction practices incorporated seismic resistant elements, for example shear keys and seismic bands. However, over time these elements have been lost as the public start underestimating the risk or they are impeded by other pressures like cost. This is a common observation internationally, especially in regions where hazards such as earthquakes have a lower return period. This means traditional knowledge is lost from communities. Returning to these local construction practices has eased their re-introduction as homeowners are already familiar with them and more likely to accept them.
The need to work with communities is especially important if new, alternative solutions are to be used. Significant awareness raising needs to be done to show communities how the building gains its strength. This is to prove that these buildings provide them adequate protection and to ensure the community can maintain the building going forward. This process must be iterative, with communities given the opportunity to provide feedback which should be reflected in designs. In Nepal this has been necessary for all solutions from cement stabilised earth brick (CSEB) construction to retrofitting. It has involved both international and national actors working over many years.
Availability and affordability of materials
Where possible materials need to be used that are available locally because local builders have experience using these materials. Using non-local materials can often lead to an increase in cost and a reduction in quality. This can be exacerbated by the often dramatic changes in availability and affordability of building materials post disaster. Whilst using new materials is not impossible, their use needs to be carefully thought through with consideration for the eventual cost to homeowners. Additionally, the local community needs to be trained not only on how to build with them, but also how to source and maintain them.
Traditional houses in Nepal are predominantly constructed using rubble stone masonry and timber. The load-bearing walls are built at least 450mm thick with two wythes of stone. The timber floors consist of joists spanning between walls and beams with the beam supported by timber posts over the height of the building.
Rubble stone has been the main building material in the mid-hills and mountainous regions of Nepal for generations, and therefore there is good knowledge of how to work with it. It is also easy and cheap to source. One particular benefit is the need to only transport it very short distances. Transport costs can significantly increase the cost of materials for homeowners due to the poor infrastructure.
Timber has also traditionally been easily available in the rural villages, and within Nepal you can see very good examples of timber workmanship. However, the timber industry is informal and the majority of timber grown in the mountainous regions is softwood which is rarely treated and poorly graded for strength. The use of timber has become unsustainable in recent years due to an increase in demand and a rise in illegal sourcing. This has resulted in a reduction in stock and an increase in price. It also creates clear cycles of environmental degradation as timber is sourced from new locations.
In Nepal bamboo is used predominantly for scaffolding and its availability is somewhat seasonal. Although it does have great potential to be used as a construction material, the seasoning of bamboo is only done at a few locations in the eastern region of Nepal. This means the cost of obtaining durable bamboo for construction in either central or western regions is very high. There is also a lack of experience designing in bamboo. For example there is only one government approved design, and there is limited social acceptance of it as a construction material.
Since the earthquake there has been a large increase in the use of block, brick and reinforced concrete. This is because people do not associate these materials with houses collapsing following the earthquake. These materials, especially reinforced concrete, have gained elevated status within Nepal. People want houses constructed of them not only due to their durability and strength, but also as a show of their wealth. However, as their use has increased it has not always come with the necessary levels of design skill or on-site workmanship that is required to ensure resilient construction.
The Government has provided mandatory rules of thumb for the design of reinforced concrete buildings. There is, however, a lack of knowledge on designing in this material. Masons do not always have the knowledge to understand and construct the specific details required. This has led to a number of new reinforced concrete buildings being non-compliant. There has been a large national and international effort to train engineers and local masons to combat this.
Obtaining approval of designs by both national and local bodies is an important step in getting communities to buy into any engineering solutions. This is especially true if they are not traditionally used in the country. Designs must be in accordance with the national building codes of the representative country, or an acceptable alternative if not available. Where possible designs should be supported by universities, engineering organisations and other relevant national and local bodies. Projects must also ensure that approval for the designs is gained at a local level, with communities and individual homeowners. Getting feedback from the end users is key in designing a lasting solution.
Following the earthquake in Nepal, which has a building code, all allowable designs that could be built as part of the reconstruction were identified and approved. This was undertaken by the National Reconstruction Authority (NRA) in its Design Catalogues for Reconstruction of Earthquake Resilient Houses Volumes I and II and the associated Repair and Retrofitting Manual for Masonry Structures. These reports identified designs ranging from one-room stone masonry in mud mortar to two-storey brick masonry in cement mortar and confined masonry to retrofitting of masonry buildings.
This process enabled new innovative designs like retrofitting, CSEB and others to gain acceptance within government and private engineering organisations. In addition, a number of these designs were developed in collaboration with Nepali universities which led to improved understanding and acceptance of the technology. Testing of the various materials (eg CSEB, hollow concrete blocks, etc) was done at their labs. This in turn has led to increased acceptance of these approaches within communities, as long as sufficient community awareness has been created.
3. Communication and awareness
Key to how communities perceive an engineering solution will be how it is communicated to them and the opportunities they are given to influence the final product. Depending on the project, this communication may need to encompass both national and local aspects. Various elements need to be considered to ensure this is done sufficiently.
Some questions to ask as part of this effort are:
What outputs to use?
How often to output information?
Is the solution aimed at a particular part of the community?
How to use model buildings/prototypes to show what is possible and act as training sites?
What will be the best way of getting community and homeowner feedback on the design?
It is also imperative that all communication takes into account existing divisions and exclusions in communities. These can often be exacerbated by disasters. Without understanding of these considerations projects can make inequalities worse and inflame tensions and conflict.
In the author’s experience the effort required to ensure good communication and awareness raising can often be much higher than expected at the outset of projects. This is especially true if they are attempting to introduce new concepts.
In Nepal people’s access to information is highly diverse and a project covers a wide area. Consequently, there is a need to do both national and local level awareness raising, with the approach differing between the two. Whilst radio, TV and other mediums can work to increase the national understanding of an approach, there is also a need to hold more local level discussions. During these discussions homeowners must be able to ask questions. They should be provided with sufficient information to fully understand the proposed solution and given the opportunity to feedback on designs. It is important that these discussions are facilitated by people who are skilled at doing this with local government and community leaders involved.
This process requires many iterations with homeowners providing feedback on:
The general design idea
How the building will be constructed and maintained
Individual preferences regarding materials used, location of openings, future flexibility and other features
In Nepal ‘model houses’ are often used to build confidence at a local level and act to promote direct feedback on the design. This is where a single house in the community is constructed using the new technique. These houses act as beacons to the community. They show them the process, enable teaching for local masons and show that the finished building is structurally strong. They also act as an example for cost and affordability. Homeowners are able to suggest changes to the design construction to make them more suitable to their situations. Whilst it is often challenging to decide whose house becomes a model house, this must be done in coordination with the community to ensure it is accepted.
Projects also need to be vigilant to increasing the expectations of a community regarding the support they will receive. It may be undesirable for an engineering solution to be seen as only relevant to a select segment of the community, or for it to only be sustainable given large amounts of additional support. For the reconstruction the large majority of homeowners have had sufficient resources to reconstruct due to the availability of government funded housing grants. However, this is not the case in all situations. Awareness raising and communication should only be carried out for communities that have the resources necessary to apply the knowledge they have gained.
For those interested in exploring the issues raised in this case study further, see the following resources:
International Federation of the Red Cross and Red Crescent Societies. (2010). Owner-Driven Housing Reconstruction Guidelines. Geneva: IFRC
Practical Action, International Federation of the Red Cross and Red Crescent Societies. (2010). PCR Tool 8: Participatory Design. Geneva: IFRC
Lyons, M., & Schilderman, T. (2010) Building Back Better: Delivering People-Centred Housing Reconstruction at Scale. Rugby: Practical Action Publishing
By Franky Ken, Principal Structural Engineer
Following the Gorkha earthquake in April 2015, I asked two architects, Liem Yusing and Yong Sylyng, to join me in a self-initiated effort to help Nepalis rebuild. We partnered and were facilitated by a small NGO based in Kathmandu, Education and Health Nepal (EHN), founded and run by Phil Palmer. This short report describes the non-technical challenges the team encountered during the three month project.
The initiative was to develop and demonstrate a transferable construction technology for typical rural housing to withstand future major earthquakes. The technology had to use locally available materials and be relatively simple. This was to encourage and empower the villagers in the hard-to-reach communities to adopt it themselves.
The project was planned in three phases:
pre-departure preparation and design
site visit and demonstration
post-departure follow up and fund raising
During the pre-departure phase, the team consulted EHN on the typology of rural housing and material availability in Nepal. We reviewed local design codes and bamboo construction, and proceeded with a prototype design. We went through several different design iterations between August and September 2015. We then arrived at the final design and specification for a typical two-storey village house. This was 4m x 6m on plan, entirely framed in bamboo with double skin walls made of woven split bamboo and plastered with mud/straw.
In October 2015, Sylyng and I flew to Nepal for the site visit and demonstration to the villagers. We were hosted and facilitated by EHN. Sylyng stayed for two weeks, while I remained for three weeks. While in Nepal we surveyed the destruction in Kathmandu city area and talked with a local city builder. We also visited schools in Dhading that survived the earthquake and spent a week in a hill village in Harkapur for the site demonstration.
Empower the villagers
Be used as a grain storage building
Act as a living laboratory to monitor the durability of the bamboo construction in Nepal’s hill climate
Serve as an exhibit for post-departure fund raising
While the team was confident in the design and technology, we were met with other challenges on the political, social and psychological fronts. As a result we had to pare down the scale of the demonstration meaning we were unable to build a full example of the design. This also meant we did not have the planned exhibit for further fundraising.
The first issue at the time was the food and fuel crisis caused by a political dispute with India. This had lead to the border closure and severe disruption in goods delivery from India. The price of fuel more than tripled when we were there. Even after agreeing to the high prices, the crisis was so severe that we had to wait for almost two weeks to find a transport to go to Harkapur, and back to Kathmandu.
Furthermore, the local builder we had previously met and agreed the budget with was no longer able to assist due to the sudden unavailability of both fuel and bamboo. Bamboo that was abundant in the weeks leading up to our visit had been cut and sold in Kathmandu to be used as construction props. The combination of a fuel crisis and rush to rebuild in the city made bamboo a highly sought-after commodity. The threefold increase in fuel cost to access other places where bamboo grows rendered it unviable.
Facing an exploding budget and running out of time, we decided to scale down the demonstration. We opted to produce a small elemental experiment to exhibit the strength of bamboo in front of the villagers. With the bamboo we did manage to obtain, we produced a sample of woven split wall to demonstrate its strength. We reached out to the members of the community to have rounds of discussions on both the strength of bamboo, despite its deceptive lightness, and their own ideas of what constitutes a house.
Here we were confronted by another challenge concerning the social and psychological aspects of the project. The villagers perceived that a permanent house must be built from solid and heavy construction materials such as stone. Furthermore, a house must be built by a certain group of people, namely, designated builders. It was not their place as farmers to build houses. While they became excited by the load tests and computer simulation videos, it simply was not enough. This is where we hoped by building one prototype we could get across and instil a deeper impression to the village communities.
Unfortunately, we did not manage to execute the project as we intended and have also been unable to follow through with the planned post-departure programme. In the ensuing months, the team learnt that the villagers had been rebuilding their houses with the method they are most familiar with, stone masonry and mud plaster.
Through this experience I learned that a humanitarian effort must be founded and executed on a base that is more than just good intentions and a brilliant idea. It cannot just be a sporadic effort parachuted into a place of need. One must invest significant effort and time to understand the unique requirements of each community and the constantly changing environment. It is also important to follow the project through to completion to ensure sustained relevance. Substantial resources are needed to deliver projects successfully.
When we started the project, we targeted a maximum construction cost of USD 1,000 per house, including both labour and material. Before the fuel crisis, the local contractor we engaged confirmed the actual cost could even be lower than our preliminary estimates. While we might have missed the opportunity to rebuild houses with the proposed scheme, should funding be available, we may still be able to demonstrate the technology. This would be by using it to build grain storage for the communities in Nepal's remote hills. In turn, with the right messaging and some good examples built, it can be possible to change people’s perceptions on the benefits of alternative appropriate forms of construction, such as certain light systems using timber and bamboo.
This article provides a realistic overview of the practical and ethical considerations when seeking to work in the sector.
Publish Date - 5 May 2020
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